1. Field of the Invention
The field of the invention relates to Magnetic Resonance Imaging (“MRI”) generally, and more particularly to certain new and useful advances in analyzing multi-coil transmit/receive (“T/R”) bias parametric data, of which the following is a specification, reference being had to the drawings accompanying and forming a part of the same.
2. Description of Related Art
Magnetic resonance (MR) imaging is a technique in which an object is placed in an electromagnetic field and subjected to pulses of the electromagnetic field at a particular frequency. The pulses cause nuclear magnetic resonance in the object and the spectra obtained thereby is processed numerically to form cross-sectional images of the object. MR imaging is especially useful for medical or veterinary applications because different living tissues emit different characteristics of resonance signals, thus enabling visualization of the different living tissues in the obtained image. An MRI apparatus thus operates in general by the application of a radio frequency (RF) electromagnetic field in the presence of other magnetic fields, and the subsequent sensing and analysis of the resulting nuclear magnetic resonances induced in the body.
Phased array multi-coils can be used in MRI to improve the signal-to-noise ratio (SNR) of images. The multi-coils allow large field of view imaging with the SNR of a small surface coil. Separate images are acquired and reconstructed from each of the elements in the multi-coil array. These separate images are then combined into a single image, with each coil dominating the spatial regions where its SNR is the highest. Typically, systems which employ a multi-coil array have an interface connected to a scanner. Each coil of the multi-coil array is electrically connected through a transmit/receive (“T/R”) bias circuit to an RF switch in the interface. The RF switch typically has a plurality of outputs that are connected to a plurality of receiver preamplifiers in the scanner. It is known in the industry that multi-coils have high parts usage, are high in replacement cost and cause an inordinately high workflow disruption.
System failures can cause a myriad of problems for their users including but limited to decreased image quality and complete inhibition of scanning. Generally, reasons for multi-coil system failures fall into one of three categories: (1) Physical damage to a coil, cable or connector, (2) T/R bias circuit failures, or (3) signal loss, noise or shadowing in images. When the failure is operator induced, it is typically due to the operator not making a suitable physical connection between the coil connectors and the system connector.
T/R bias circuit failures may be due to hardware failures or pending hardware failures in the T/R circuitry itself. If the failure is due to hardware malfunctions, it is often times difficult to tell if it is a true hardware failure or merely an operator induced failure. Also, often times there may be signs that the T/R circuitry is failing, and if not dealt with appropriately, may lead to system degradation or system failure and, in turn, ultimately lead to workflow disruption.
Presently, certain systems may be equipped with data monitoring systems that track and store fault data associated with the system. For example, Phillips Healthcare, in pamphlet number 4522 962 36291/800 ©August 2008, provides a remote services system that shares data and monitors equipment from a remote location. In the system provided by Philips, adjustments to equipment may be made remotely of scheduled to be completed during routine service calls. Siemens AG, in White Paper Pamphlet published in December 2009, discloses a remote systems analysis capable of detecting and repairing problems with equipment, in some instances. For example, in this pamphlet at page 6, Siemens describes a system for a CT scanner in which the scanner is preloaded with more than 10 sensors that are constantly monitoring the tube functions, the sensors then communicate any detected problems back to a service team.
There are many drawbacks with the above-described ad hoc approaches. One problem it is such approaches focus on the technician's ability to recognize, from a potentially complicated data set, a potential fault condition. Another problem is that even if the technician properly recognizes a fault condition, it assumes he or she will take the proper remedial steps, and that it would be extremely costly and labor intensive for a technician to constantly monitor and analyze data from the T/R circuitry, so much so that it is not feasible. In the case of systems that electronically monitor data, the analysis is not forward thinking and predicative, but rather reactive to a problem that may be taking place at that given time.
Accordingly, to date, no suitable system or method for monitoring, acquiring and analyzing multi-coil fault data exists.